Spinal Reflex
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The spinal cord sends and receives information to and from the brain. It is continuous with the brain stem.

3 Types of neurons:

1) AFFERENT- sensory n
erves carry information from the body to the brain.
2) EFFERENT- motor nerves carry information from th e brain to the body.
3) INTERNEURONS- carry information between 2 neurons.

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Grey Matter- butterfly shaped center portion of the spinal cord.
It is the location of CELL BODIES in the spinal cord.

Dorsal Ganglion- dilated area.
- site of the AFFERENT neurons CELL BODY.

Ventral Nerve Root- the region from the spinal cord to the spinal nerve containing only MOTOR fibers.
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Dorsal Nerve Root- the region from the spinal cord to the posterior spinal cord containing only SENSORY fibers.
- dorsal ganglion is found here.

Receptor- nerve ending that MONITORS CHANGES IN THE EXTERNAL ENVIRONMENT.
- initiate a sensory neuron’s action potential

Effector- tissue supplied by a motor neuron

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Spinal Nerve- sensory information travels up the afferent fiber and directly stimulates the efferent neuron in the anterior grey horn of the spinal cord.
- Efferent fiber then sends a signal to a muscle to move the body.